Critical · published April 2, 2024
In the Linux kernel, the following vulnerability has been resolved:
tunnels: fix out of bounds access when building IPv6 PMTU error
If the ICMPv6 error is built from a non-linear skb we get the following
splat,
BUG: KASAN: slab-out-of-bounds in do_csum+0x220/0x240
Read of size 4 at addr ffff88811d402c80 by task netperf/820
CPU: 0 PID: 820 Comm: netperf Not tainted 6.8.0-rc1+ #543
...
kasan_report+0xd8/0x110
do_csum+0x220/0x240
csum_partial+0xc/0x20
skb_tunnel_check_pmtu+0xeb9/0x3280
vxlan_xmit_one+0x14c2/0x4080
vxlan_xmit+0xf61/0x5c00
dev_hard_start_xmit+0xfb/0x510
__dev_queue_xmit+0x7cd/0x32a0
br_dev_queue_push_xmit+0x39d/0x6a0
Use skb_checksum instead of csum_partial who cannot deal with non-linear
SKBs.
| Product | Versions | Fixed in |
|---|---|---|
| linux/linux_kernel | ≥ 5.9, < 5.10.210 | 5.10.210 |
| linux/linux_kernel | ≥ 5.11, < 5.15.149 | 5.15.149 |
| linux/linux_kernel | ≥ 5.16, < 6.1.78 | 6.1.78 |
| linux/linux_kernel | ≥ 6.2, < 6.6.17 | 6.6.17 |
| linux/linux_kernel | ≥ 6.7, < 6.7.5 | 6.7.5 |
| linux/linux_kernel | all versions | — |
| linux/linux_kernel | all versions | — |
| linux/linux_kernel | all versions | — |
| debian/debian_linux | all versions | — |